Flue-scraper



(No Model.)

G.'H. PASSETT 8; J. ELDER.

FLUE SGRAPER.

No. 566,973. Patented Sept. 1, 1896.

NITED STATES PATE T rrrcn.

GEORGE H. FASSETT AND JOHN ELDER, OF CHICAGO, ILLINOIS.

FLUE-SCRAPER.

SPECIFICATION forming part of Letters Patent No. 566,973, datedSeptember 1, 1896.

5. Serial No. 589,874. (No model.)

To (LZZ whom [it Null/0071106771,:

Be it known that we, GEORGE H. FAssETT and JOHN ELDER, of Chicago,Illinois, have invented certain new and useful Improvements inFlue-Scrapers, of which the following is a specification.

This invention relates to that class of devices which are used forscraping or cleaning the interior of the flues of steamboilers; and theinvention consists in a flue-scraper having a series of scraping blades,knives, or sections which are spring-supported in such manner that theyare automatically thrust out into contact with the interior wall of theflue, the device being thereby automatic and the knives operating undera constant springpressure.

The preferred form of the invention is illustrated in the accompanyingdrawings, in which- Figure 1 is a longitudinal section of the tube orfine, showing the scraper therein, partly in section and partly inelevation. Fig. 2 is a transverse section through the tube, showing thescraper in end elevation. Fig. 3 is a longitudinal sectional viewthrough the tube, showing the seraper in side elevation. Figs. 4 and 5are detail views, respectively, of the knife-supporting ring and one ofthe knives, the latter being shown in edge and side view.

In the drawings, A represents a boiler-tube. The scraper, in thepreferred construction, comprises a body B, which is conveniently formedfrom a section of pipe threaded on its ends and having the caps O D, thelatter having an interiorly-threaded neck (Z, into which a handle E maybe turned.

F represents a knife supporting ring. (Shown detached in Fig. 4.) It maybe driven or shrunk onto the body B and is provided with peripheralslots f and bolt-apertures f.

G represents the scrapers or knife-secti0ns, of which any suitablenumber may be em ployed, three being shown. These sections areconstructed in the form of curved seg- 'ments, and their ends arereduced in thickness, as shown at g, to adapt the sections to overlapeach other, as indicated by the dotted lines in Fig. 2 and in theelevation in Fig. 3. They are movably supported on the ring F by thebolts H with nuts h. These knifesections are spring-supported by meansof the spring-rods I, which pass through apertures g in theknife-sections and have their ends entering apertures b in the tubularbody B. The spring-rods normally tend, being under tension, by reason ofthe engagement of their bent ends with the tubular body, to thrust theknife-sections out into contact with the inner walls of thetube, andthey are sufficiently yielding to permit the implement to be thrust intothe tube and to be moved back and forth for cleaning the inner surfacethereof. The sections are therefore automatically adjustable to a slightdegree to accommodate themselves to the variations in the sizes of thetubes, although by preference the implement will be proportioned to theparticular caliber of tube with which it is employed, and theknife-sections are normally supported, 1'. a, when free from pressure,so that their edges form a circle of slightly greater diameter than thebore of the tube, thereby making the knives operate underspring-tension.

Owing to the heat to which the implement is subjected it may be foundthat the springrods I will become inefficient by loss of temper. Toguard against this, we may employ the reinforce-springs, arrangedinternally of the tubular body, and which, as shown, are fiat strips ofmetal J, secured at their outer ends by screws and bearing at theirinner ends upon sliding pins K which project through apertures in thewall of the tubular body and operate against the inner edges of theknife-sections. These reinforce-springs may be dispensed with. When itbecomes necessary or desirable to change the springs, either to replacethose which have become inefficient or for the purpose of varying thesize of the scraper, by the removal of the bolts H the knife-sectionsmay be lifted out and new springs put in place, and by applying springsof different length or, what amounts to the same, of a differentcurvature the ef fective or operative size of the implement may bevaried.

\Vithout limiting our invention to precise details of construction, weclaim.-

In a flue-scraper the combination with a the body, and reinforce-springsarranged tubular body having an operating-handle, a Within the tubularbody, substantially as de- 10 knife-supporting ring" secured thereon,knifescribed.

sections having; slotted openings therein, GEORGE H. FASSETT. 5 boltsfor slidably connecting the knife-sec- J OIIN ELDER.

tions with the ring, spring-rods passing Witnesses:

through apertures in the knife-sections and C. O. LINTHICUM,

having their ends removably engaged with FREDERICK C. GOODWIN.

